Apparatus for the manufacture of induction-coils.



'No. 804,250. PATENTBD NOV. 14, 1905.

L. B. MILLER. APPARATUS FOR THE MANUFACTURE OF INDUCTION GOILS.

APPLICATION FILED MAR.9, 1904.

4 SHEETS-SHEET l.

xuwukiiikll" 4 Jill illllllillllllllll mmnuqnmm PATENTED NOV. 14, 1905.

' L. B. MILLER. APPARATUS FOR THE MANUFACTURE OF INDUCTION COILS.

APPLICATION FILED MAR.9,1904.

I 4 SHBETS-$HBBT 2.

1731 A 43 d h?" JZZarvzy No. 804,250. PATENTED NOV. 14, 1905. L. B.MILLER.

APPARATUS FOR THE MANUFACTURE OF INDUCTION COILS.

APPLICATION FILED MAR.9, 1904.

4 SHEETSSHBET 3.

PATENTED NOV. 14, 1905.

L. B. MILLER. APPARATUS FOR THE MANUFACTURE OF INDUCTION G APPLI ATION rED AR. 1904 OILS.

UNITED STATES PATENT OFFICE LESLIE BRADLEY MILLER, OF LONDON, ENGLAND.APPARATUS FOR THE MANUFACTURE OF INDUCTION-COILS.

Specification of Letters Patent.

Patented Nov.'14, 1905.

To all whom it may concern:

Be it known that I, LESLIE BRADLEY MIL- LER, a subject of the King ofGreat Britain and Ireland, residing in London,England,have inventedImprovements in and Apparatus for the Manufacture of Induction-Coils, ofwhich the following is a specification.

This invention relates to the construction of high-tension coils forinduction-coils or other electric apparatus. In theory each section ofthe high-tension portion of such a coil should consist of one wire woundon itself in such a way that each convolution lies on the.

top of the one Wound immediately before it, like a clock-spring. Inpractice the sections of large induction-coils, such as are used forwireless telegraphy and X-rays apparatus, are usually each about twomillimeters thick, the wire being wound between two disks placed thisdistance apart, with the result that owing to irregular winding itoftenhappens that convolutions of wire between which a considerabledifference of potential obtains come close together and sooner or latercause short-circuiting of a small portion'of the winding. This seriouslyinterferes with the efficiency of the coil and generally leads to acomplete breakdown of the coil.

Now the present invention has reference to the manufacture of thehigh-tension portions of induction-coils of line wire-for example, No.36 standard wire-gage-that is to say,

1 wire having a diameter of about .2 millimeter-the wire being wound inflat spirals like a clock-spring of any required diameter, one wirethick, and with any predetermined distance between the adjacentconvolutions of wire, the winding of the wire being effected from theinner to the outer circumference of one spiral and back again from theouter to the inner circumference of the next spiral, and so on withoutany break in the continuity of the wire until the end of the wire isreached. A section of an induction-coil, comprising, for example, ahundred or more flat helices of the kind described, each one wire thickand totaling up to about one and a half to two inches in axialthickness, is then for convenience taken off the winding-machine andsubjected to considerable pressure while warm, so as to convert-it intoa solid or compact block. The outer end of the wire is then joined toanother section of flat helices made in a similar way and the other endof which is connected to a third section, and so on to form a secondarywinding of the desired length to form, in conjunction with a primarywinding, an induction-coil of the required power. By the constructiondescribed there are very few joints in the whole of the secondarywinding of the ind uction-coil, and even these are wholly on the outsideof the coil.

The invention consists in-the novel form of induction-coil hereinaftermore particularly specified in the claims. In the accompanyingillustrative drawings, Figures 1, 2, and 3 show, respectively, in sideelevation, plan, and end elevation apparatus suitable for winding flathelices of fine wire according to this invention. Fig. 4; shows, to alarger scale, a device hereinafter called a guide, which both guides thewire into its desired position on the surface to which it is to beattached and presses it upon such surface so that it will then remain inplace, at the same time allowing the following portion of wire to slidecontinuously under it. Fig. 5 shows the guide combined with a heatingand cutting device. Fig. 6 is a diagrammatic View. Figs. 7 and 8 show,respectively, in

sectional side elevation and plan a modified construction of. windingapparatus. Fig. 9 shows diagrammatically three fiat insulated helices offine wire wound on three insulating-disks according to this invention.

Referring to Figs. 1 to 6, inclusive, a is a circular metal' platemounted on a spindle 5 so as to revolve, preferably horizontally. It isdriven from a hand-wheel 0 through a shaft (land bevel-gearing c, On theface of the plate a ring :22, of paper, is stuck, having its surfacecoated with paraiIin-wax. Onto this coated ringfineinsulated wire A isdrawn from a revolving drum f, Figs. 2 and 6, over a suitably-groovedroller 9, Figs. 4, 5, and 6, so arranged that the wire emerges at anangle to the plate a from under a guide it close to the parafiinedpaper, the drumf being mounted to turn quite freely. The guide has agrooved rear side and a flat lower side and is pressed down by a spiralspring h, Fig. 1, and is geared so as to travel outward and inward alonga radius of the disk at a suitable rate and causes the wire A to be laidon and also pressed into the surface of the ring it in a clock-springhelix. For this purpose, in the example now being described, the guideit is carried by a rod Z1, that extends through a cylindrical holder m,carried by a lever 72, that is mounted to turn and slide endwise upon ahorizontal rod 0 and is provided with a halfnut 10, that engages a screwq. This screw is rotated by a toothed wheel 9", driven from a pinion son the shaft 01 through reversing interchangeable wheels 6 t and t. Justin front of the guide it there may be provided a metal blade M, Fig. 5,adapted to act as a plow and cut a fine groove in the surface of theparaffinwax, into which the wire falls. The cutter may be heated by aspiral of resistance-wire 'U wound round it and heated electrically; orit may be warmed by a gas-flame, so as to melt the wax slightly. Itworks well if placed just where the wire ceases to hold on the surfaceof the ring of paper, in which case it should follow the guide. The waxcools and sets round the wire as the diskrecedes, thus keeping thewinding firmly in the desired position on the surface.

The wire may be pressed in by a roller following the cutter or guide,and an independent motion can be given to the roller, so as to cause thedisk to revolve under it. I find, however, in practice that the heatedcut-ter or plow may be dispensed with if the-wire be coated with a hotliquid insulating'material as, for example, by drawing it'through meltedparaflin wax in a vessel w, Fig. 6. This warms the wire, and if it bethen pressed by the guide it upon a layer of slightly warm paraffin-waxmade by brushing over the surface of the paper ring 00 with a brushdipped in hot wax it will readily adhere and remain in the position inwhich it is wound, no matter whether the convolutions of wire are soclose as to touch one another or whether there is a small space betweeneach in order to obtain the highest insulation between the convolutions.When one helix wound from center to circumference is finished, a paperring is placed over it, and the next may be wound from circumference tocenter after changing the direction of motion of the guide It, asbymoving the wheels 2? t t endwise, without any break beingmade in thecontinuity of the wire.

To avoid making a joint or cutting the paper ring right-acrbss one sidefor the third layer, the wire should be threaded through the ring. ofthese rings'are threaded over the wire before the winding is commenced,as shown at w in Fig. 6, and, being held in asuitable clip are taken oneby one as required. Each ring is slit for a part of its width to allowof the wire passing through it at the-inner or outer periphery of thehelix, as shown at as in Fig. 9.

By proceeding in the manner de scribed tinewire coils of any size can bemade with jointless sections, Fig. 9, without any ointed ends from whichwasteful brush discharges can take place and secure from possibility ofbreakdown; i In a coil so constructed the sections thereof'can be safelyforced together with considerable pressure without danger of shortlated.

In practice a considerable number' circuiting any of the convolutions,thereby enabling greater efiiciency to be attained by diminishing brushdischarge. The insulation between the convolutions of each helix is alsoimproved, as the convolutions are not wound in contact with one another,but are each fixed independently upon an insulating-surface, with aspace of any determined width between the successive convolutions, suchspace being variable at will by altering the velocity ratio between therevolving bed and radial guide.

.If the electric tension between two helices is only to be moderatelyhigh, no paper disk need be used, and one helix can be wound directly onthe other or for convenience on a thin metal disk that is slit on oneside and which can then be afterward freed from the wire by athin-bladed knife and withdrawn, or the direction of winding may bereversed,

. so that when the metal disk is turned over and the wire separated fromit by the application of heat current will flow in the same directionthrough both helices.

Instead of using insulated w-ire bare Wire may be employed, each turnbeing separated from the next by a narrow space, which may or may not befilled with insulating material. The wire may be heated by passing acurrent through an inch or more of it between the guide 71 and theroller g, which is then insu- It is the possibility wire thatconstitutes a marked distinction between coils constructed according tothis invention and all other coils wound in vertical sections ofwhatever width in which successive convolutions are wound more or lesson the top of one another in the manner already described and in whichthe coil could not work at all if bare wire were used, as the wholelength of wire would be short-circuited upon itself and act like a metaldisk.

Instead of passing the wire through hot .paraflin, Fig.6, otherinsulating materials can be used, such as a mixture of several parts ofresin to one of boiled linseed-oil. A surface of paper or otherinsulator coated with these will remain sufiiciently adhesive for somedays to hold the wire in position Without the use of heat, and there isthen no necessity to pass the'wire through a bath of liquid insulatingmaterial, or'th e guide spectively, in Figs. 7 and 8, be moved radiallyby connecting it to a horizontal slide-rod 1, to which is also connectedapin 2, (hereinafter called a feeler,) the lower end of which is notchedto engage a scroll-thread 3 of A section cut in the surface of ahorizontal plate 4, suitably geared to the horizontal table a. The plateand table may, as shown, be rotated continuously in the same directionfrom the shaft d through bevel-gearing e and e. In this case the radialinward movement of the guide it can be effected by engaging the feeler 2with the outer right-hand portion of the of winding with bare k may, asshown, re-

thread 3 and rotating the plate 4 in the direc- 1 tion of the arrow. Theradial outward movement of the guide it is effected by disengaging thefeeler2 from the inner end portion of the thread 3 at one side of thecenter of motion and engaging it with the outer left-hand portion of thethread at the diametrically opposite side of the center of motion. ablethis to be done, the feeler 2 may be arranged to be lifted out ofengagement with the thread 3 and the portion of the slide-rod l carryingit be moved endwise to the necessary extent into a holder 5, fixed tothe portion of the slide-rod carrying the guide It.

This arrangement also admits of the making of coils of differentdiameters, or the sliderod may, as shown. be provided with twovertically-movable feelers 2 and 2*, adapted to be engaged alternatelywith diametrically oppositeportions of the thread 3 and to be held in araised inoperative position, or instead of shifting the single feelerfrom one side of the center of motion to the other or using two feelersa single feeler may be used and the radial inward and outward motion ofthe guide it be produced by reversing the direction of motion of thescroll-plate 4, the table a being continuously rotated in the samedirection.

The scroll-plate 4 may, as shown, be rotated at a slower rate than tablea, so as to admit of the use of a coarse thread 3 thereon. Also thetable a may be made vertically adjustable, so that it can be loweredfrom time to time to prevent undue compression of the spring h, andtherefore undue pressure be tween the guide it and the insulatingmaterial on which it bears, caused by accumulation of superim posedhelices of wire on the table. For this purpose the shaft carrying thetable may be made in two parts 6 1), arranged telescopically one withinthe other and detachably connected together by a screw 6 By suitablyaltering the gearing between the rotary table and radially-movablewireguiding device any desired distance can be produced between thesuccessive convolutions of .wire in the helices of wire produced by themachine.

As it is impracticable to windthick wire by the method described, inorder to increase the cross-section several fine wires may be wound sideby side or several helices may be con- 1 nected in parallel.

To en- What I claim is 1. As a new article of-manufacture, a section ofhigh-tension winding for an inductioncoil, comprising a number of flatconnected helices of fine wire, each helix being composed of a singlewire wound in a single plane, and insulating material that is normallysolid but is capable of being softened and which is arranged to separateand hold the he lices from 'each other and by which eachconvolution ofwire is separately held in place.

2. As a new article of manufacture, a section'of high-tension windingfor an inductioncoil, comprising anumber of flat connected helices offine wire each formed of'a single Wire wound in a single plane, sheetinsulating material separating the successive helices from each otherand insulating material that is normally solid but is capable of beingsoftened applied to the sheet insulating material and by which eachconvolution of wire is held separately in place.

As a new article of manufacture, a section of high-tension winding foran inductioncoil, comprising a number of fiat helices of fine wireconnected together alternately at their inner and outer peripheries andformed of a continuous length of wire,-each helix being composed of wirewound in a single plane, and insulating material that is normally solidbut is capable of being softened separating the helices from each otherand by which each convolution of wire is held separately in place.

4:. As a new article of manufacture, a hightension section for-aninduction-coil, comprising a number of flat helices of fine wireconnected together alternately at their inner and outer peripheries andformed from a continuous length of wire each helix being composed ofwire wound in a single plane, and sheet insulating material separatingthe successive helices from each other, and insulating material that isnormally solid but is capable of being softened applied to the sheetinsulating material and by which each convolution of wire is separatelyheld in place.

Signed at London, England, this 18th day of January, 1904.

LESLIE BRADLEY MILLER.

Witnesses:

H. D. JAMEsoN, A. NUTTINJG.

IOO

